d03a217466
Provide a drop_dead_args() function which deletes them instead. We still need to assign a register to dead EBB arguments, so they can't just be ignored.
1352 lines
46 KiB
Rust
1352 lines
46 KiB
Rust
//! Function layout.
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//!
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//! The order of extended basic blocks in a function and the order of instructions in an EBB is
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//! determined by the `Layout` data structure defined in this module.
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use std::cmp;
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use std::iter::{Iterator, IntoIterator};
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use entity_map::EntityMap;
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use packed_option::PackedOption;
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use ir::entities::{Ebb, Inst};
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use ir::progpoint::{ProgramOrder, ExpandedProgramPoint};
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/// The `Layout` struct determines the layout of EBBs and instructions in a function. It does not
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/// contain definitions of instructions or EBBs, but depends on `Inst` and `Ebb` entity references
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/// being defined elsewhere.
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///
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/// This data structure determines:
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///
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/// - The order of EBBs in the function.
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/// - Which EBB contains a given instruction.
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/// - The order of instructions with an EBB.
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///
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/// While data dependencies are not recorded, instruction ordering does affect control
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/// dependencies, so part of the semantics of the program are determined by the layout.
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///
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#[derive(Clone)]
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pub struct Layout {
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// Linked list nodes for the layout order of EBBs Forms a doubly linked list, terminated in
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// both ends by `None`.
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ebbs: EntityMap<Ebb, EbbNode>,
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// Linked list nodes for the layout order of instructions. Forms a double linked list per EBB,
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// terminated in both ends by `None`.
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insts: EntityMap<Inst, InstNode>,
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// First EBB in the layout order, or `None` when no EBBs have been laid out.
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first_ebb: Option<Ebb>,
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// Last EBB in the layout order, or `None` when no EBBs have been laid out.
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last_ebb: Option<Ebb>,
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}
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impl Layout {
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/// Create a new empty `Layout`.
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pub fn new() -> Layout {
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Layout {
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ebbs: EntityMap::new(),
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insts: EntityMap::new(),
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first_ebb: None,
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last_ebb: None,
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}
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}
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}
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// Sequence numbers.
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//
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// All instructions and EBBs are given a sequence number that can be used to quickly determine
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// their relative position in the layout. The sequence numbers are not contiguous, but are assigned
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// like line numbers in BASIC: 10, 20, 30, ...
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//
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// The EBB sequence numbers are strictly increasing, and so are the instruction sequence numbers
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// within an EBB. The instruction sequence numbers are all between the sequence number of their
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// containing EBB and the following EBB.
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//
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// The result is that sequence numbers work like BASIC line numbers for the textual representation
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// of the IL.
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type SequenceNumber = u32;
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// Initial stride assigned to new sequence numbers.
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const MAJOR_STRIDE: SequenceNumber = 10;
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// Secondary stride used when renumbering locally.
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const MINOR_STRIDE: SequenceNumber = 2;
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// Compute the midpoint between `a` and `b`.
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// Return `None` if the midpoint would be equal to either.
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fn midpoint(a: SequenceNumber, b: SequenceNumber) -> Option<SequenceNumber> {
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assert!(a < b);
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// Avoid integer overflow.
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let m = a + (b - a) / 2;
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if m > a { Some(m) } else { None }
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}
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#[test]
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fn test_midpoint() {
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assert_eq!(midpoint(0, 1), None);
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assert_eq!(midpoint(0, 2), Some(1));
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assert_eq!(midpoint(0, 3), Some(1));
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assert_eq!(midpoint(0, 4), Some(2));
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assert_eq!(midpoint(1, 4), Some(2));
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assert_eq!(midpoint(2, 4), Some(3));
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assert_eq!(midpoint(3, 4), None);
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assert_eq!(midpoint(3, 4), None);
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}
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impl ProgramOrder for Layout {
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fn cmp<A, B>(&self, a: A, b: B) -> cmp::Ordering
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where A: Into<ExpandedProgramPoint>,
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B: Into<ExpandedProgramPoint>
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{
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let a_seq = self.seq(a);
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let b_seq = self.seq(b);
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a_seq.cmp(&b_seq)
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}
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fn is_ebb_gap(&self, inst: Inst, ebb: Ebb) -> bool {
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let i = &self.insts[inst];
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let e = &self.ebbs[ebb];
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i.next.is_none() && i.ebb == e.prev
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}
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}
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// Private methods for dealing with sequence numbers.
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impl Layout {
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/// Get the sequence number of a program point that must correspond to an entity in the layout.
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fn seq<PP: Into<ExpandedProgramPoint>>(&self, pp: PP) -> SequenceNumber {
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// When `PP = Inst` or `PP = Ebb`, we expect this dynamic type check to be optimized out.
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match pp.into() {
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ExpandedProgramPoint::Ebb(ebb) => self.ebbs[ebb].seq,
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ExpandedProgramPoint::Inst(inst) => self.insts[inst].seq,
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}
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}
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/// Get the last sequence number in `ebb`.
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fn last_ebb_seq(&self, ebb: Ebb) -> SequenceNumber {
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// Get the seq of the last instruction if it exists, otherwise use the EBB header seq.
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self.ebbs[ebb]
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.last_inst
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.map(|inst| self.insts[inst].seq)
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.unwrap_or(self.ebbs[ebb].seq)
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}
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/// Assign a valid sequence number to `ebb` such that the numbers are still monotonic. This may
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/// require renumbering.
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fn assign_ebb_seq(&mut self, ebb: Ebb) {
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assert!(self.is_ebb_inserted(ebb));
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// Get the sequence number immediately before `ebb`, or 0.
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let prev_seq = self.ebbs[ebb]
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.prev
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.map(|prev_ebb| self.last_ebb_seq(prev_ebb))
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.unwrap_or(0);
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// Get the sequence number immediately following `ebb`.
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let next_seq = if let Some(inst) = self.ebbs[ebb].first_inst.expand() {
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self.insts[inst].seq
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} else if let Some(next_ebb) = self.ebbs[ebb].next.expand() {
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self.ebbs[next_ebb].seq
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} else {
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// There is nothing after `ebb`. We can just use a major stride.
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self.ebbs[ebb].seq = prev_seq + MAJOR_STRIDE;
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return;
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};
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// Check if there is room between these sequence numbers.
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if let Some(seq) = midpoint(prev_seq, next_seq) {
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self.ebbs[ebb].seq = seq;
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} else {
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// No available integers between `prev_seq` and `next_seq`. We have to renumber.
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self.renumber_from_ebb(ebb, prev_seq + MINOR_STRIDE);
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}
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}
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/// Assign a valid sequence number to `inst` such that the numbers are still monotonic. This may
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/// require renumbering.
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fn assign_inst_seq(&mut self, inst: Inst) {
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let ebb = self.inst_ebb(inst)
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.expect("inst must be inserted before assigning an seq");
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// Get the sequence number immediately before `inst`.
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let prev_seq = match self.insts[inst].prev.expand() {
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Some(prev_inst) => self.insts[prev_inst].seq,
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None => self.ebbs[ebb].seq,
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};
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// Get the sequence number immediately following `inst`.
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let next_seq = if let Some(next_inst) = self.insts[inst].next.expand() {
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self.insts[next_inst].seq
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} else if let Some(next_ebb) = self.ebbs[ebb].next.expand() {
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self.ebbs[next_ebb].seq
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} else {
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// There is nothing after `inst`. We can just use a major stride.
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self.insts[inst].seq = prev_seq + MAJOR_STRIDE;
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return;
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};
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// Check if there is room between these sequence numbers.
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if let Some(seq) = midpoint(prev_seq, next_seq) {
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self.insts[inst].seq = seq;
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} else {
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// No available integers between `prev_seq` and `next_seq`. We have to renumber.
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self.renumber_from_inst(inst, prev_seq + MINOR_STRIDE);
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}
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}
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/// Renumber instructions starting from `inst` until the end of the EBB or until numbers catch
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/// up.
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///
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/// Return `None` if renumbering has caught up and the sequence is monotonic again. Otherwise
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/// return the last used sequence number.
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fn renumber_insts(&mut self, inst: Inst, seq: SequenceNumber) -> Option<SequenceNumber> {
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let mut inst = inst;
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let mut seq = seq;
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loop {
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self.insts[inst].seq = seq;
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// Next instruction.
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inst = match self.insts[inst].next.expand() {
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None => return Some(seq),
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Some(next) => next,
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};
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if seq < self.insts[inst].seq {
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// Sequence caught up.
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return None;
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}
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seq += MINOR_STRIDE;
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}
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}
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/// Renumber starting from `ebb` to `seq` and continuing until the sequence numbers are
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/// monotonic again.
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fn renumber_from_ebb(&mut self, ebb: Ebb, first_seq: SequenceNumber) {
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let mut ebb = ebb;
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let mut seq = first_seq;
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loop {
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self.ebbs[ebb].seq = seq;
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// Renumber instructions in `ebb`. Stop when the numbers catch up.
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if let Some(inst) = self.ebbs[ebb].first_inst.expand() {
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seq = match self.renumber_insts(inst, seq + MINOR_STRIDE) {
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Some(s) => s,
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None => return,
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}
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}
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// Advance to the next EBB.
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ebb = match self.ebbs[ebb].next.expand() {
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Some(next) => next,
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None => return,
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};
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// Stop renumbering once the numbers catch up.
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if seq < self.ebbs[ebb].seq {
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return;
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}
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seq += MINOR_STRIDE;
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}
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}
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/// Renumber starting from `inst` to `seq` and continuing until the sequence numbers are
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/// monotonic again.
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fn renumber_from_inst(&mut self, inst: Inst, first_seq: SequenceNumber) {
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if let Some(seq) = self.renumber_insts(inst, first_seq) {
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// Renumbering spills over into next EBB.
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if let Some(next_ebb) = self.ebbs[self.inst_ebb(inst).unwrap()].next.expand() {
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self.renumber_from_ebb(next_ebb, seq + MINOR_STRIDE);
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}
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}
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}
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}
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/// Methods for laying out EBBs.
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///
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/// An unknown EBB starts out as *not inserted* in the EBB layout. The layout is a linear order of
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/// inserted EBBs. Once an EBB has been inserted in the layout, instructions can be added. An EBB
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/// can only be removed from the layout when it is empty.
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///
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/// Since every EBB must end with a terminator instruction which cannot fall through, the layout of
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/// EBBs do not affect the semantics of the program.
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///
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impl Layout {
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/// Is `ebb` currently part of the layout?
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pub fn is_ebb_inserted(&self, ebb: Ebb) -> bool {
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Some(ebb) == self.first_ebb || (self.ebbs.is_valid(ebb) && self.ebbs[ebb].prev.is_some())
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}
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/// Insert `ebb` as the last EBB in the layout.
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pub fn append_ebb(&mut self, ebb: Ebb) {
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assert!(!self.is_ebb_inserted(ebb),
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"Cannot append EBB that is already in the layout");
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{
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let node = self.ebbs.ensure(ebb);
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assert!(node.first_inst.is_none() && node.last_inst.is_none());
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node.prev = self.last_ebb.into();
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node.next = None.into();
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}
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if let Some(last) = self.last_ebb {
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self.ebbs[last].next = ebb.into();
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} else {
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self.first_ebb = Some(ebb);
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}
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self.last_ebb = Some(ebb);
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self.assign_ebb_seq(ebb);
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}
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/// Insert `ebb` in the layout before the existing EBB `before`.
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pub fn insert_ebb(&mut self, ebb: Ebb, before: Ebb) {
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assert!(!self.is_ebb_inserted(ebb),
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"Cannot insert EBB that is already in the layout");
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assert!(self.is_ebb_inserted(before),
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"EBB Insertion point not in the layout");
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let after = self.ebbs[before].prev;
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{
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let node = self.ebbs.ensure(ebb);
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node.next = before.into();
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node.prev = after;
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}
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self.ebbs[before].prev = ebb.into();
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match after.expand() {
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None => self.first_ebb = Some(ebb),
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Some(a) => self.ebbs[a].next = ebb.into(),
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}
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self.assign_ebb_seq(ebb);
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}
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/// Insert `ebb` in the layout *after* the existing EBB `after`.
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pub fn insert_ebb_after(&mut self, ebb: Ebb, after: Ebb) {
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assert!(!self.is_ebb_inserted(ebb),
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"Cannot insert EBB that is already in the layout");
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assert!(self.is_ebb_inserted(after),
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"EBB Insertion point not in the layout");
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let before = self.ebbs[after].next;
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{
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let node = self.ebbs.ensure(ebb);
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node.next = before;
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node.prev = after.into();
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}
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self.ebbs[after].next = ebb.into();
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match before.expand() {
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None => self.last_ebb = Some(ebb),
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Some(b) => self.ebbs[b].prev = ebb.into(),
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}
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self.assign_ebb_seq(ebb);
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}
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/// Return an iterator over all EBBs in layout order.
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pub fn ebbs<'f>(&'f self) -> Ebbs<'f> {
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Ebbs {
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layout: self,
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next: self.first_ebb,
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}
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}
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/// Get the function's entry block.
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/// This is simply the first EBB in the layout order.
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pub fn entry_block(&self) -> Option<Ebb> {
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self.first_ebb
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}
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/// Get the block following `ebb` in the layout order.
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pub fn next_ebb(&self, ebb: Ebb) -> Option<Ebb> {
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self.ebbs[ebb].next.expand()
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}
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}
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#[derive(Clone, Debug, Default)]
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struct EbbNode {
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prev: PackedOption<Ebb>,
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next: PackedOption<Ebb>,
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first_inst: PackedOption<Inst>,
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last_inst: PackedOption<Inst>,
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seq: SequenceNumber,
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}
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|
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/// Iterate over EBBs in layout order. See `Layout::ebbs()`.
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pub struct Ebbs<'f> {
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layout: &'f Layout,
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next: Option<Ebb>,
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}
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impl<'f> Iterator for Ebbs<'f> {
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type Item = Ebb;
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fn next(&mut self) -> Option<Ebb> {
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match self.next {
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Some(ebb) => {
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self.next = self.layout.ebbs[ebb].next.expand();
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Some(ebb)
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}
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None => None,
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}
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}
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}
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|
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/// Use a layout reference in a for loop.
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impl<'f> IntoIterator for &'f Layout {
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type Item = Ebb;
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type IntoIter = Ebbs<'f>;
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|
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fn into_iter(self) -> Ebbs<'f> {
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self.ebbs()
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}
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}
|
|
|
|
/// Methods for arranging instructions.
|
|
///
|
|
/// An instruction starts out as *not inserted* in the layout. An instruction can be inserted into
|
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/// an EBB at a given position.
|
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impl Layout {
|
|
/// Get the EBB containing `inst`, or `None` if `inst` is not inserted in the layout.
|
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pub fn inst_ebb(&self, inst: Inst) -> Option<Ebb> {
|
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if self.insts.is_valid(inst) {
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self.insts[inst].ebb.into()
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} else {
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None
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}
|
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}
|
|
|
|
/// Append `inst` to the end of `ebb`.
|
|
pub fn append_inst(&mut self, inst: Inst, ebb: Ebb) {
|
|
assert_eq!(self.inst_ebb(inst), None);
|
|
assert!(self.is_ebb_inserted(ebb),
|
|
"Cannot append instructions to EBB not in layout");
|
|
{
|
|
let ebb_node = &mut self.ebbs[ebb];
|
|
{
|
|
let inst_node = self.insts.ensure(inst);
|
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inst_node.ebb = ebb.into();
|
|
inst_node.prev = ebb_node.last_inst;
|
|
assert!(inst_node.next.is_none());
|
|
}
|
|
if ebb_node.first_inst.is_none() {
|
|
ebb_node.first_inst = inst.into();
|
|
} else {
|
|
self.insts[ebb_node.last_inst.unwrap()].next = inst.into();
|
|
}
|
|
ebb_node.last_inst = inst.into();
|
|
}
|
|
self.assign_inst_seq(inst);
|
|
}
|
|
|
|
/// Fetch an ebb's first instruction.
|
|
pub fn first_inst(&self, ebb: Ebb) -> Option<Inst> {
|
|
self.ebbs[ebb].first_inst.into()
|
|
}
|
|
|
|
/// Fetch an ebb's last instruction.
|
|
pub fn last_inst(&self, ebb: Ebb) -> Option<Inst> {
|
|
self.ebbs[ebb].last_inst.into()
|
|
}
|
|
|
|
/// Insert `inst` before the instruction `before` in the same EBB.
|
|
pub fn insert_inst(&mut self, inst: Inst, before: Inst) {
|
|
assert_eq!(self.inst_ebb(inst), None);
|
|
let ebb = self.inst_ebb(before)
|
|
.expect("Instruction before insertion point not in the layout");
|
|
let after = self.insts[before].prev;
|
|
{
|
|
let inst_node = self.insts.ensure(inst);
|
|
inst_node.ebb = ebb.into();
|
|
inst_node.next = before.into();
|
|
inst_node.prev = after;
|
|
}
|
|
self.insts[before].prev = inst.into();
|
|
match after.expand() {
|
|
None => self.ebbs[ebb].first_inst = inst.into(),
|
|
Some(a) => self.insts[a].next = inst.into(),
|
|
}
|
|
self.assign_inst_seq(inst);
|
|
}
|
|
|
|
/// Remove `inst` from the layout.
|
|
pub fn remove_inst(&mut self, inst: Inst) {
|
|
let ebb = self.inst_ebb(inst)
|
|
.expect("Instruction already removed.");
|
|
// Clear the `inst` node and extract links.
|
|
let prev;
|
|
let next;
|
|
{
|
|
let n = &mut self.insts[inst];
|
|
prev = n.prev;
|
|
next = n.next;
|
|
n.ebb = None.into();
|
|
n.prev = None.into();
|
|
n.next = None.into();
|
|
}
|
|
// Fix up links to `inst`.
|
|
match prev.expand() {
|
|
None => self.ebbs[ebb].first_inst = next,
|
|
Some(p) => self.insts[p].next = next,
|
|
}
|
|
match next.expand() {
|
|
None => self.ebbs[ebb].last_inst = prev,
|
|
Some(n) => self.insts[n].prev = prev,
|
|
}
|
|
}
|
|
|
|
/// Iterate over the instructions in `ebb` in layout order.
|
|
pub fn ebb_insts<'f>(&'f self, ebb: Ebb) -> Insts<'f> {
|
|
Insts {
|
|
layout: self,
|
|
head: self.ebbs[ebb].first_inst.into(),
|
|
tail: self.ebbs[ebb].last_inst.into(),
|
|
}
|
|
}
|
|
|
|
/// Split the EBB containing `before` in two.
|
|
///
|
|
/// Insert `new_ebb` after the old EBB and move `before` and the following instructions to
|
|
/// `new_ebb`:
|
|
///
|
|
/// ```text
|
|
/// old_ebb:
|
|
/// i1
|
|
/// i2
|
|
/// i3 << before
|
|
/// i4
|
|
/// ```
|
|
/// becomes:
|
|
///
|
|
/// ```text
|
|
/// old_ebb:
|
|
/// i1
|
|
/// i2
|
|
/// new_ebb:
|
|
/// i3 << before
|
|
/// i4
|
|
/// ```
|
|
pub fn split_ebb(&mut self, new_ebb: Ebb, before: Inst) {
|
|
let old_ebb = self.inst_ebb(before)
|
|
.expect("The `before` instruction must be in the layout");
|
|
assert!(!self.is_ebb_inserted(new_ebb));
|
|
|
|
// Insert new_ebb after old_ebb.
|
|
let next_ebb = self.ebbs[old_ebb].next;
|
|
let last_inst = self.ebbs[old_ebb].last_inst;
|
|
{
|
|
let node = self.ebbs.ensure(new_ebb);
|
|
node.prev = old_ebb.into();
|
|
node.next = next_ebb;
|
|
node.first_inst = before.into();
|
|
node.last_inst = last_inst;
|
|
}
|
|
self.ebbs[old_ebb].next = new_ebb.into();
|
|
|
|
// Fix backwards link.
|
|
if Some(old_ebb) == self.last_ebb {
|
|
self.last_ebb = Some(new_ebb);
|
|
} else {
|
|
self.ebbs[next_ebb.unwrap()].prev = new_ebb.into();
|
|
}
|
|
|
|
// Disconnect the instruction links.
|
|
let prev_inst = self.insts[before].prev;
|
|
self.insts[before].prev = None.into();
|
|
self.ebbs[old_ebb].last_inst = prev_inst;
|
|
match prev_inst.expand() {
|
|
None => self.ebbs[old_ebb].first_inst = None.into(),
|
|
Some(pi) => self.insts[pi].next = None.into(),
|
|
}
|
|
|
|
// Fix the instruction -> ebb pointers.
|
|
let mut opt_i = Some(before);
|
|
while let Some(i) = opt_i {
|
|
debug_assert_eq!(self.insts[i].ebb.expand(), Some(old_ebb));
|
|
self.insts[i].ebb = new_ebb.into();
|
|
opt_i = self.insts[i].next.into();
|
|
}
|
|
|
|
self.assign_ebb_seq(new_ebb);
|
|
}
|
|
}
|
|
|
|
#[derive(Clone, Debug, Default)]
|
|
struct InstNode {
|
|
// The Ebb containing this instruction, or `None` if the instruction is not yet inserted.
|
|
ebb: PackedOption<Ebb>,
|
|
prev: PackedOption<Inst>,
|
|
next: PackedOption<Inst>,
|
|
seq: SequenceNumber,
|
|
}
|
|
|
|
/// Iterate over instructions in an EBB in layout order. See `Layout::ebb_insts()`.
|
|
pub struct Insts<'f> {
|
|
layout: &'f Layout,
|
|
head: Option<Inst>,
|
|
tail: Option<Inst>,
|
|
}
|
|
|
|
impl<'f> Iterator for Insts<'f> {
|
|
type Item = Inst;
|
|
|
|
fn next(&mut self) -> Option<Inst> {
|
|
let rval = self.head;
|
|
if let Some(inst) = rval {
|
|
if self.head == self.tail {
|
|
self.head = None;
|
|
self.tail = None;
|
|
} else {
|
|
self.head = self.layout.insts[inst].next.into();
|
|
}
|
|
}
|
|
rval
|
|
}
|
|
}
|
|
|
|
impl<'f> DoubleEndedIterator for Insts<'f> {
|
|
fn next_back(&mut self) -> Option<Inst> {
|
|
let rval = self.tail;
|
|
if let Some(inst) = rval {
|
|
if self.head == self.tail {
|
|
self.head = None;
|
|
self.tail = None;
|
|
} else {
|
|
self.tail = self.layout.insts[inst].prev.into();
|
|
}
|
|
}
|
|
rval
|
|
}
|
|
}
|
|
|
|
|
|
/// Layout Cursor.
|
|
///
|
|
/// A `Cursor` represents a position in a function layout where instructions can be inserted and
|
|
/// removed. It can be used to iterate through the instructions of a function while editing them at
|
|
/// the same time. A normal instruction iterator can't do this since it holds an immutable
|
|
/// reference to the Layout.
|
|
///
|
|
/// When new instructions are added, the cursor can either append them to an EBB or insert them
|
|
/// before the current instruction.
|
|
pub struct Cursor<'f> {
|
|
/// Borrowed function layout. Public so it can be re-borrowed from this cursor.
|
|
pub layout: &'f mut Layout,
|
|
pos: CursorPosition,
|
|
}
|
|
|
|
/// The possible positions of a cursor.
|
|
#[derive(Clone, Copy, PartialEq, Eq, Debug)]
|
|
pub enum CursorPosition {
|
|
/// Cursor is not pointing anywhere. No instructions can be inserted.
|
|
Nowhere,
|
|
/// Cursor is pointing at an existing instruction.
|
|
/// New instructions will be inserted *before* the current instruction.
|
|
At(Inst),
|
|
/// Cursor is before the beginning of an EBB. No instructions can be inserted. Calling
|
|
/// `next_inst()` will move to the first instruction in the EBB.
|
|
Before(Ebb),
|
|
/// Cursor is pointing after the end of an EBB.
|
|
/// New instructions will be appended to the EBB.
|
|
After(Ebb),
|
|
}
|
|
|
|
impl<'f> Cursor<'f> {
|
|
/// Create a new `Cursor` for `layout`.
|
|
/// The cursor holds a mutable reference to `layout` for its entire lifetime.
|
|
pub fn new(layout: &'f mut Layout) -> Cursor {
|
|
Cursor {
|
|
layout,
|
|
pos: CursorPosition::Nowhere,
|
|
}
|
|
}
|
|
|
|
/// Get the current position.
|
|
pub fn position(&self) -> CursorPosition {
|
|
self.pos
|
|
}
|
|
|
|
/// Move the cursor to a new position.
|
|
pub fn set_position(&mut self, pos: CursorPosition) {
|
|
self.pos = pos;
|
|
}
|
|
|
|
/// Get the EBB corresponding to the current position.
|
|
pub fn current_ebb(&self) -> Option<Ebb> {
|
|
use self::CursorPosition::*;
|
|
match self.pos {
|
|
Nowhere => None,
|
|
At(inst) => self.layout.inst_ebb(inst),
|
|
Before(ebb) | After(ebb) => Some(ebb),
|
|
}
|
|
}
|
|
|
|
/// Get the instruction corresponding to the current position, if any.
|
|
pub fn current_inst(&self) -> Option<Inst> {
|
|
use self::CursorPosition::*;
|
|
match self.pos {
|
|
At(inst) => Some(inst),
|
|
_ => None,
|
|
}
|
|
}
|
|
|
|
/// Go to a specific instruction which must be inserted in the layout.
|
|
/// New instructions will be inserted before `inst`.
|
|
pub fn goto_inst(&mut self, inst: Inst) {
|
|
assert!(self.layout.inst_ebb(inst).is_some());
|
|
self.pos = CursorPosition::At(inst);
|
|
}
|
|
|
|
/// Go to the top of `ebb` which must be inserted into the layout.
|
|
/// At this position, instructions cannot be inserted, but `next_inst()` will move to the first
|
|
/// instruction in `ebb`.
|
|
pub fn goto_top(&mut self, ebb: Ebb) {
|
|
assert!(self.layout.is_ebb_inserted(ebb));
|
|
self.pos = CursorPosition::Before(ebb);
|
|
}
|
|
|
|
/// Go to the bottom of `ebb` which must be inserted into the layout.
|
|
/// At this position, inserted instructions will be appended to `ebb`.
|
|
pub fn goto_bottom(&mut self, ebb: Ebb) {
|
|
assert!(self.layout.is_ebb_inserted(ebb));
|
|
self.pos = CursorPosition::After(ebb);
|
|
}
|
|
|
|
/// Go to the top of the next EBB in layout order and return it.
|
|
///
|
|
/// - If the cursor wasn't pointing at anything, go to the top of the first EBB in the
|
|
/// function.
|
|
/// - If there are no more EBBs, leave the cursor pointing at nothing and return `None`.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// The `next_ebb()` method is intended for iterating over the EBBs in layout order:
|
|
///
|
|
/// ```
|
|
/// # use cretonne::ir::{Function, Ebb};
|
|
/// # use cretonne::ir::layout::Cursor;
|
|
/// fn edit_func(func: &mut Function) {
|
|
/// let mut cursor = Cursor::new(&mut func.layout);
|
|
/// while let Some(ebb) = cursor.next_ebb() {
|
|
/// // Edit ebb.
|
|
/// }
|
|
/// }
|
|
/// ```
|
|
pub fn next_ebb(&mut self) -> Option<Ebb> {
|
|
let next = if let Some(ebb) = self.current_ebb() {
|
|
self.layout.ebbs[ebb].next.expand()
|
|
} else {
|
|
self.layout.first_ebb
|
|
};
|
|
self.pos = match next {
|
|
Some(ebb) => CursorPosition::Before(ebb),
|
|
None => CursorPosition::Nowhere,
|
|
};
|
|
next
|
|
}
|
|
|
|
/// Go to the bottom of the previous EBB in layout order and return it.
|
|
///
|
|
/// - If the cursor wasn't pointing at anything, go to the bottom of the last EBB in the
|
|
/// function.
|
|
/// - If there are no more EBBs, leave the cursor pointing at nothing and return `None`.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// The `prev_ebb()` method is intended for iterating over the EBBs in backwards layout order:
|
|
///
|
|
/// ```
|
|
/// # use cretonne::ir::{Function, Ebb};
|
|
/// # use cretonne::ir::layout::Cursor;
|
|
/// fn edit_func(func: &mut Function) {
|
|
/// let mut cursor = Cursor::new(&mut func.layout);
|
|
/// while let Some(ebb) = cursor.prev_ebb() {
|
|
/// // Edit ebb.
|
|
/// }
|
|
/// }
|
|
/// ```
|
|
pub fn prev_ebb(&mut self) -> Option<Ebb> {
|
|
let prev = if let Some(ebb) = self.current_ebb() {
|
|
self.layout.ebbs[ebb].prev.expand()
|
|
} else {
|
|
self.layout.last_ebb
|
|
};
|
|
self.pos = match prev {
|
|
Some(ebb) => CursorPosition::After(ebb),
|
|
None => CursorPosition::Nowhere,
|
|
};
|
|
prev
|
|
}
|
|
|
|
/// Move to the next instruction in the same EBB and return it.
|
|
///
|
|
/// - If the cursor was positioned before an EBB, go to the first instruction in that EBB.
|
|
/// - If there are no more instructions in the EBB, go to the `After(ebb)` position and return
|
|
/// `None`.
|
|
/// - If the cursor wasn't pointing anywhere, keep doing that.
|
|
///
|
|
/// This method will never move the cursor to a different EBB.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// The `next_inst()` method is intended for iterating over the instructions in an EBB like
|
|
/// this:
|
|
///
|
|
/// ```
|
|
/// # use cretonne::ir::{Function, Ebb};
|
|
/// # use cretonne::ir::layout::Cursor;
|
|
/// fn edit_ebb(func: &mut Function, ebb: Ebb) {
|
|
/// let mut cursor = Cursor::new(&mut func.layout);
|
|
/// cursor.goto_top(ebb);
|
|
/// while let Some(inst) = cursor.next_inst() {
|
|
/// // Edit instructions...
|
|
/// }
|
|
/// }
|
|
/// ```
|
|
/// The loop body can insert and remove instructions via the cursor.
|
|
///
|
|
/// Iterating over all the instructions in a function looks like this:
|
|
///
|
|
/// ```
|
|
/// # use cretonne::ir::{Function, Ebb};
|
|
/// # use cretonne::ir::layout::Cursor;
|
|
/// fn edit_func(func: &mut Function) {
|
|
/// let mut cursor = Cursor::new(&mut func.layout);
|
|
/// while let Some(ebb) = cursor.next_ebb() {
|
|
/// while let Some(inst) = cursor.next_inst() {
|
|
/// // Edit instructions...
|
|
/// }
|
|
/// }
|
|
/// }
|
|
/// ```
|
|
pub fn next_inst(&mut self) -> Option<Inst> {
|
|
use self::CursorPosition::*;
|
|
match self.pos {
|
|
Nowhere | After(..) => None,
|
|
At(inst) => {
|
|
if let Some(next) = self.layout.insts[inst].next.expand() {
|
|
self.pos = At(next);
|
|
Some(next)
|
|
} else {
|
|
self.pos = After(self.layout
|
|
.inst_ebb(inst)
|
|
.expect("current instruction removed?"));
|
|
None
|
|
}
|
|
}
|
|
Before(ebb) => {
|
|
if let Some(next) = self.layout.ebbs[ebb].first_inst.expand() {
|
|
self.pos = At(next);
|
|
Some(next)
|
|
} else {
|
|
self.pos = After(ebb);
|
|
None
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Move to the previous instruction in the same EBB and return it.
|
|
///
|
|
/// - If the cursor was positioned after an EBB, go to the last instruction in that EBB.
|
|
/// - If there are no more instructions in the EBB, go to the `Before(ebb)` position and return
|
|
/// `None`.
|
|
/// - If the cursor wasn't pointing anywhere, keep doing that.
|
|
///
|
|
/// This method will never move the cursor to a different EBB.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// The `prev_inst()` method is intended for iterating backwards over the instructions in an
|
|
/// EBB like this:
|
|
///
|
|
/// ```
|
|
/// # use cretonne::ir::{Function, Ebb};
|
|
/// # use cretonne::ir::layout::Cursor;
|
|
/// fn edit_ebb(func: &mut Function, ebb: Ebb) {
|
|
/// let mut cursor = Cursor::new(&mut func.layout);
|
|
/// cursor.goto_bottom(ebb);
|
|
/// while let Some(inst) = cursor.prev_inst() {
|
|
/// // Edit instructions...
|
|
/// }
|
|
/// }
|
|
/// ```
|
|
pub fn prev_inst(&mut self) -> Option<Inst> {
|
|
use self::CursorPosition::*;
|
|
match self.pos {
|
|
Nowhere | Before(..) => None,
|
|
At(inst) => {
|
|
if let Some(prev) = self.layout.insts[inst].prev.expand() {
|
|
self.pos = At(prev);
|
|
Some(prev)
|
|
} else {
|
|
self.pos = Before(self.layout
|
|
.inst_ebb(inst)
|
|
.expect("current instruction removed?"));
|
|
None
|
|
}
|
|
}
|
|
After(ebb) => {
|
|
if let Some(prev) = self.layout.ebbs[ebb].last_inst.expand() {
|
|
self.pos = At(prev);
|
|
Some(prev)
|
|
} else {
|
|
self.pos = Before(ebb);
|
|
None
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Insert an instruction at the current position.
|
|
///
|
|
/// - If pointing at an instruction, the new instruction is inserted before the current
|
|
/// instruction.
|
|
/// - If pointing at the bottom of an EBB, the new instruction is appended to the EBB.
|
|
/// - Otherwise panic.
|
|
///
|
|
/// In either case, the cursor is not moved, such that repeated calls to `insert_inst()` causes
|
|
/// instructions to appear in insertion order in the EBB.
|
|
pub fn insert_inst(&mut self, inst: Inst) {
|
|
use self::CursorPosition::*;
|
|
match self.pos {
|
|
Nowhere | Before(..) => panic!("Invalid insert_inst position"),
|
|
At(cur) => self.layout.insert_inst(inst, cur),
|
|
After(ebb) => self.layout.append_inst(inst, ebb),
|
|
}
|
|
}
|
|
|
|
/// Remove the instruction under the cursor.
|
|
///
|
|
/// The cursor is left pointing at the position following the current instruction.
|
|
///
|
|
/// Return the instruction that was removed.
|
|
pub fn remove_inst(&mut self) -> Inst {
|
|
let inst = self.current_inst().expect("No instruction to remove");
|
|
self.next_inst();
|
|
self.layout.remove_inst(inst);
|
|
inst
|
|
}
|
|
|
|
/// Insert an EBB at the current position and switch to it.
|
|
///
|
|
/// As far as possible, this method behaves as if the EBB header were an instruction inserted
|
|
/// at the current position.
|
|
///
|
|
/// - If the cursor is pointing at an existing instruction, *the current EBB is split in two*
|
|
/// and the current instruction becomes the first instruction in the inserted EBB.
|
|
/// - If the cursor points at the bottom of an EBB, the new EBB is inserted after the current
|
|
/// one, and moved to the bottom of the new EBB where instructions can be appended.
|
|
/// - If the cursor points to the top of an EBB, the new EBB is inserted above the current one.
|
|
/// - If the cursor is not pointing at anything, the new EBB is placed last in the layout.
|
|
///
|
|
/// This means that is is always valid to call this method, and it always leaves the cursor in
|
|
/// a state that will insert instructions into the new EBB.
|
|
pub fn insert_ebb(&mut self, new_ebb: Ebb) {
|
|
use self::CursorPosition::*;
|
|
match self.pos {
|
|
At(inst) => {
|
|
self.layout.split_ebb(new_ebb, inst);
|
|
// All other cases move to `After(ebb)`, but in this case we we'll stay `At(inst)`.
|
|
return;
|
|
}
|
|
Nowhere => self.layout.append_ebb(new_ebb),
|
|
Before(ebb) => self.layout.insert_ebb(new_ebb, ebb),
|
|
After(ebb) => self.layout.insert_ebb_after(new_ebb, ebb),
|
|
}
|
|
// For everything but `At(inst)` we end up appending to the new EBB.
|
|
self.pos = After(new_ebb);
|
|
}
|
|
}
|
|
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::{Layout, Cursor, CursorPosition};
|
|
use entity_map::EntityRef;
|
|
use ir::{Ebb, Inst, ProgramOrder};
|
|
use std::cmp::Ordering;
|
|
|
|
fn verify(layout: &mut Layout, ebbs: &[(Ebb, &[Inst])]) {
|
|
// Check that EBBs are inserted and instructions belong the right places.
|
|
// Check forward linkage with iterators.
|
|
// Check that layout sequence numbers are strictly monotonic.
|
|
{
|
|
let mut seq = 0;
|
|
let mut ebb_iter = layout.ebbs();
|
|
for &(ebb, insts) in ebbs {
|
|
assert!(layout.is_ebb_inserted(ebb));
|
|
assert_eq!(ebb_iter.next(), Some(ebb));
|
|
assert!(layout.ebbs[ebb].seq > seq);
|
|
seq = layout.ebbs[ebb].seq;
|
|
|
|
let mut inst_iter = layout.ebb_insts(ebb);
|
|
for &inst in insts {
|
|
assert_eq!(layout.inst_ebb(inst), Some(ebb));
|
|
assert_eq!(inst_iter.next(), Some(inst));
|
|
assert!(layout.insts[inst].seq > seq);
|
|
seq = layout.insts[inst].seq;
|
|
}
|
|
assert_eq!(inst_iter.next(), None);
|
|
}
|
|
assert_eq!(ebb_iter.next(), None);
|
|
}
|
|
|
|
// Check backwards linkage with a cursor.
|
|
let mut cur = Cursor::new(layout);
|
|
for &(ebb, insts) in ebbs.into_iter().rev() {
|
|
assert_eq!(cur.prev_ebb(), Some(ebb));
|
|
for &inst in insts.into_iter().rev() {
|
|
assert_eq!(cur.prev_inst(), Some(inst));
|
|
}
|
|
assert_eq!(cur.prev_inst(), None);
|
|
}
|
|
assert_eq!(cur.prev_ebb(), None);
|
|
}
|
|
|
|
#[test]
|
|
fn append_ebb() {
|
|
let mut layout = Layout::new();
|
|
let e0 = Ebb::new(0);
|
|
let e1 = Ebb::new(1);
|
|
let e2 = Ebb::new(2);
|
|
|
|
{
|
|
let imm = &layout;
|
|
assert!(!imm.is_ebb_inserted(e0));
|
|
assert!(!imm.is_ebb_inserted(e1));
|
|
}
|
|
verify(&mut layout, &[]);
|
|
|
|
layout.append_ebb(e1);
|
|
assert!(!layout.is_ebb_inserted(e0));
|
|
assert!(layout.is_ebb_inserted(e1));
|
|
assert!(!layout.is_ebb_inserted(e2));
|
|
let v: Vec<Ebb> = layout.ebbs().collect();
|
|
assert_eq!(v, [e1]);
|
|
|
|
layout.append_ebb(e2);
|
|
assert!(!layout.is_ebb_inserted(e0));
|
|
assert!(layout.is_ebb_inserted(e1));
|
|
assert!(layout.is_ebb_inserted(e2));
|
|
let v: Vec<Ebb> = layout.ebbs().collect();
|
|
assert_eq!(v, [e1, e2]);
|
|
|
|
layout.append_ebb(e0);
|
|
assert!(layout.is_ebb_inserted(e0));
|
|
assert!(layout.is_ebb_inserted(e1));
|
|
assert!(layout.is_ebb_inserted(e2));
|
|
let v: Vec<Ebb> = layout.ebbs().collect();
|
|
assert_eq!(v, [e1, e2, e0]);
|
|
|
|
{
|
|
let imm = &layout;
|
|
let mut v = Vec::new();
|
|
for e in imm {
|
|
v.push(e);
|
|
}
|
|
assert_eq!(v, [e1, e2, e0]);
|
|
}
|
|
|
|
// Test cursor positioning.
|
|
let mut cur = Cursor::new(&mut layout);
|
|
assert_eq!(cur.position(), CursorPosition::Nowhere);
|
|
assert_eq!(cur.next_inst(), None);
|
|
assert_eq!(cur.position(), CursorPosition::Nowhere);
|
|
assert_eq!(cur.prev_inst(), None);
|
|
assert_eq!(cur.position(), CursorPosition::Nowhere);
|
|
|
|
assert_eq!(cur.next_ebb(), Some(e1));
|
|
assert_eq!(cur.position(), CursorPosition::Before(e1));
|
|
assert_eq!(cur.next_inst(), None);
|
|
assert_eq!(cur.position(), CursorPosition::After(e1));
|
|
assert_eq!(cur.next_inst(), None);
|
|
assert_eq!(cur.position(), CursorPosition::After(e1));
|
|
assert_eq!(cur.next_ebb(), Some(e2));
|
|
assert_eq!(cur.prev_inst(), None);
|
|
assert_eq!(cur.position(), CursorPosition::Before(e2));
|
|
assert_eq!(cur.next_ebb(), Some(e0));
|
|
assert_eq!(cur.next_ebb(), None);
|
|
assert_eq!(cur.position(), CursorPosition::Nowhere);
|
|
|
|
// Backwards through the EBBs.
|
|
assert_eq!(cur.prev_ebb(), Some(e0));
|
|
assert_eq!(cur.position(), CursorPosition::After(e0));
|
|
assert_eq!(cur.prev_ebb(), Some(e2));
|
|
assert_eq!(cur.prev_ebb(), Some(e1));
|
|
assert_eq!(cur.prev_ebb(), None);
|
|
assert_eq!(cur.position(), CursorPosition::Nowhere);
|
|
}
|
|
|
|
#[test]
|
|
fn insert_ebb() {
|
|
let mut layout = Layout::new();
|
|
let e0 = Ebb::new(0);
|
|
let e1 = Ebb::new(1);
|
|
let e2 = Ebb::new(2);
|
|
|
|
{
|
|
let imm = &layout;
|
|
assert!(!imm.is_ebb_inserted(e0));
|
|
assert!(!imm.is_ebb_inserted(e1));
|
|
|
|
let v: Vec<Ebb> = layout.ebbs().collect();
|
|
assert_eq!(v, []);
|
|
}
|
|
|
|
layout.append_ebb(e1);
|
|
assert!(!layout.is_ebb_inserted(e0));
|
|
assert!(layout.is_ebb_inserted(e1));
|
|
assert!(!layout.is_ebb_inserted(e2));
|
|
verify(&mut layout, &[(e1, &[])]);
|
|
|
|
layout.insert_ebb(e2, e1);
|
|
assert!(!layout.is_ebb_inserted(e0));
|
|
assert!(layout.is_ebb_inserted(e1));
|
|
assert!(layout.is_ebb_inserted(e2));
|
|
verify(&mut layout, &[(e2, &[]), (e1, &[])]);
|
|
|
|
layout.insert_ebb(e0, e1);
|
|
assert!(layout.is_ebb_inserted(e0));
|
|
assert!(layout.is_ebb_inserted(e1));
|
|
assert!(layout.is_ebb_inserted(e2));
|
|
verify(&mut layout, &[(e2, &[]), (e0, &[]), (e1, &[])]);
|
|
}
|
|
|
|
#[test]
|
|
fn insert_ebb_after() {
|
|
let mut layout = Layout::new();
|
|
let e0 = Ebb::new(0);
|
|
let e1 = Ebb::new(1);
|
|
let e2 = Ebb::new(2);
|
|
|
|
layout.append_ebb(e1);
|
|
layout.insert_ebb_after(e2, e1);
|
|
verify(&mut layout, &[(e1, &[]), (e2, &[])]);
|
|
|
|
layout.insert_ebb_after(e0, e1);
|
|
verify(&mut layout, &[(e1, &[]), (e0, &[]), (e2, &[])]);
|
|
}
|
|
|
|
#[test]
|
|
fn append_inst() {
|
|
let mut layout = Layout::new();
|
|
let e1 = Ebb::new(1);
|
|
|
|
layout.append_ebb(e1);
|
|
let v: Vec<Inst> = layout.ebb_insts(e1).collect();
|
|
assert_eq!(v, []);
|
|
|
|
let i0 = Inst::new(0);
|
|
let i1 = Inst::new(1);
|
|
let i2 = Inst::new(2);
|
|
|
|
assert_eq!(layout.inst_ebb(i0), None);
|
|
assert_eq!(layout.inst_ebb(i1), None);
|
|
assert_eq!(layout.inst_ebb(i2), None);
|
|
|
|
layout.append_inst(i1, e1);
|
|
assert_eq!(layout.inst_ebb(i0), None);
|
|
assert_eq!(layout.inst_ebb(i1), Some(e1));
|
|
assert_eq!(layout.inst_ebb(i2), None);
|
|
let v: Vec<Inst> = layout.ebb_insts(e1).collect();
|
|
assert_eq!(v, [i1]);
|
|
|
|
layout.append_inst(i2, e1);
|
|
assert_eq!(layout.inst_ebb(i0), None);
|
|
assert_eq!(layout.inst_ebb(i1), Some(e1));
|
|
assert_eq!(layout.inst_ebb(i2), Some(e1));
|
|
let v: Vec<Inst> = layout.ebb_insts(e1).collect();
|
|
assert_eq!(v, [i1, i2]);
|
|
|
|
// Test double-ended instruction iterator.
|
|
let v: Vec<Inst> = layout.ebb_insts(e1).rev().collect();
|
|
assert_eq!(v, [i2, i1]);
|
|
|
|
layout.append_inst(i0, e1);
|
|
verify(&mut layout, &[(e1, &[i1, i2, i0])]);
|
|
|
|
// Test cursor positioning.
|
|
let mut cur = Cursor::new(&mut layout);
|
|
cur.goto_top(e1);
|
|
assert_eq!(cur.position(), CursorPosition::Before(e1));
|
|
assert_eq!(cur.prev_inst(), None);
|
|
assert_eq!(cur.position(), CursorPosition::Before(e1));
|
|
assert_eq!(cur.next_inst(), Some(i1));
|
|
assert_eq!(cur.position(), CursorPosition::At(i1));
|
|
assert_eq!(cur.next_inst(), Some(i2));
|
|
assert_eq!(cur.next_inst(), Some(i0));
|
|
assert_eq!(cur.prev_inst(), Some(i2));
|
|
assert_eq!(cur.position(), CursorPosition::At(i2));
|
|
assert_eq!(cur.next_inst(), Some(i0));
|
|
assert_eq!(cur.position(), CursorPosition::At(i0));
|
|
assert_eq!(cur.next_inst(), None);
|
|
assert_eq!(cur.position(), CursorPosition::After(e1));
|
|
assert_eq!(cur.next_inst(), None);
|
|
assert_eq!(cur.position(), CursorPosition::After(e1));
|
|
assert_eq!(cur.prev_inst(), Some(i0));
|
|
assert_eq!(cur.prev_inst(), Some(i2));
|
|
assert_eq!(cur.prev_inst(), Some(i1));
|
|
assert_eq!(cur.prev_inst(), None);
|
|
assert_eq!(cur.position(), CursorPosition::Before(e1));
|
|
|
|
// Test remove_inst.
|
|
cur.goto_inst(i2);
|
|
assert_eq!(cur.remove_inst(), i2);
|
|
verify(cur.layout, &[(e1, &[i1, i0])]);
|
|
assert_eq!(cur.layout.inst_ebb(i2), None);
|
|
assert_eq!(cur.remove_inst(), i0);
|
|
verify(cur.layout, &[(e1, &[i1])]);
|
|
assert_eq!(cur.layout.inst_ebb(i0), None);
|
|
assert_eq!(cur.position(), CursorPosition::After(e1));
|
|
cur.layout.remove_inst(i1);
|
|
verify(cur.layout, &[(e1, &[])]);
|
|
assert_eq!(cur.layout.inst_ebb(i1), None);
|
|
}
|
|
|
|
#[test]
|
|
fn insert_inst() {
|
|
let mut layout = Layout::new();
|
|
let e1 = Ebb::new(1);
|
|
|
|
layout.append_ebb(e1);
|
|
let v: Vec<Inst> = layout.ebb_insts(e1).collect();
|
|
assert_eq!(v, []);
|
|
|
|
let i0 = Inst::new(0);
|
|
let i1 = Inst::new(1);
|
|
let i2 = Inst::new(2);
|
|
|
|
assert_eq!(layout.inst_ebb(i0), None);
|
|
assert_eq!(layout.inst_ebb(i1), None);
|
|
assert_eq!(layout.inst_ebb(i2), None);
|
|
|
|
layout.append_inst(i1, e1);
|
|
assert_eq!(layout.inst_ebb(i0), None);
|
|
assert_eq!(layout.inst_ebb(i1), Some(e1));
|
|
assert_eq!(layout.inst_ebb(i2), None);
|
|
let v: Vec<Inst> = layout.ebb_insts(e1).collect();
|
|
assert_eq!(v, [i1]);
|
|
|
|
layout.insert_inst(i2, i1);
|
|
assert_eq!(layout.inst_ebb(i0), None);
|
|
assert_eq!(layout.inst_ebb(i1), Some(e1));
|
|
assert_eq!(layout.inst_ebb(i2), Some(e1));
|
|
let v: Vec<Inst> = layout.ebb_insts(e1).collect();
|
|
assert_eq!(v, [i2, i1]);
|
|
|
|
layout.insert_inst(i0, i1);
|
|
verify(&mut layout, &[(e1, &[i2, i0, i1])]);
|
|
}
|
|
|
|
#[test]
|
|
fn multiple_ebbs() {
|
|
let mut layout = Layout::new();
|
|
|
|
let e0 = Ebb::new(0);
|
|
let e1 = Ebb::new(1);
|
|
|
|
assert_eq!(layout.entry_block(), None);
|
|
layout.append_ebb(e0);
|
|
assert_eq!(layout.entry_block(), Some(e0));
|
|
layout.append_ebb(e1);
|
|
assert_eq!(layout.entry_block(), Some(e0));
|
|
|
|
let i0 = Inst::new(0);
|
|
let i1 = Inst::new(1);
|
|
let i2 = Inst::new(2);
|
|
let i3 = Inst::new(3);
|
|
|
|
layout.append_inst(i0, e0);
|
|
layout.append_inst(i1, e0);
|
|
layout.append_inst(i2, e1);
|
|
layout.append_inst(i3, e1);
|
|
|
|
let v0: Vec<Inst> = layout.ebb_insts(e0).collect();
|
|
let v1: Vec<Inst> = layout.ebb_insts(e1).collect();
|
|
assert_eq!(v0, [i0, i1]);
|
|
assert_eq!(v1, [i2, i3]);
|
|
}
|
|
|
|
#[test]
|
|
fn split_ebb() {
|
|
let mut layout = Layout::new();
|
|
|
|
let e0 = Ebb::new(0);
|
|
let e1 = Ebb::new(1);
|
|
let e2 = Ebb::new(2);
|
|
|
|
let i0 = Inst::new(0);
|
|
let i1 = Inst::new(1);
|
|
let i2 = Inst::new(2);
|
|
let i3 = Inst::new(3);
|
|
|
|
layout.append_ebb(e0);
|
|
layout.append_inst(i0, e0);
|
|
assert_eq!(layout.inst_ebb(i0), Some(e0));
|
|
layout.split_ebb(e1, i0);
|
|
assert_eq!(layout.inst_ebb(i0), Some(e1));
|
|
|
|
{
|
|
let mut cur = Cursor::new(&mut layout);
|
|
assert_eq!(cur.next_ebb(), Some(e0));
|
|
assert_eq!(cur.next_inst(), None);
|
|
assert_eq!(cur.next_ebb(), Some(e1));
|
|
assert_eq!(cur.next_inst(), Some(i0));
|
|
assert_eq!(cur.next_inst(), None);
|
|
assert_eq!(cur.next_ebb(), None);
|
|
|
|
// Check backwards links.
|
|
assert_eq!(cur.prev_ebb(), Some(e1));
|
|
assert_eq!(cur.prev_inst(), Some(i0));
|
|
assert_eq!(cur.prev_inst(), None);
|
|
assert_eq!(cur.prev_ebb(), Some(e0));
|
|
assert_eq!(cur.prev_inst(), None);
|
|
assert_eq!(cur.prev_ebb(), None);
|
|
}
|
|
|
|
layout.append_inst(i1, e0);
|
|
layout.append_inst(i2, e0);
|
|
layout.append_inst(i3, e0);
|
|
layout.split_ebb(e2, i2);
|
|
|
|
assert_eq!(layout.inst_ebb(i0), Some(e1));
|
|
assert_eq!(layout.inst_ebb(i1), Some(e0));
|
|
assert_eq!(layout.inst_ebb(i2), Some(e2));
|
|
assert_eq!(layout.inst_ebb(i3), Some(e2));
|
|
|
|
{
|
|
let mut cur = Cursor::new(&mut layout);
|
|
assert_eq!(cur.next_ebb(), Some(e0));
|
|
assert_eq!(cur.next_inst(), Some(i1));
|
|
assert_eq!(cur.next_inst(), None);
|
|
assert_eq!(cur.next_ebb(), Some(e2));
|
|
assert_eq!(cur.next_inst(), Some(i2));
|
|
assert_eq!(cur.next_inst(), Some(i3));
|
|
assert_eq!(cur.next_inst(), None);
|
|
assert_eq!(cur.next_ebb(), Some(e1));
|
|
assert_eq!(cur.next_inst(), Some(i0));
|
|
assert_eq!(cur.next_inst(), None);
|
|
assert_eq!(cur.next_ebb(), None);
|
|
|
|
assert_eq!(cur.prev_ebb(), Some(e1));
|
|
assert_eq!(cur.prev_inst(), Some(i0));
|
|
assert_eq!(cur.prev_inst(), None);
|
|
assert_eq!(cur.prev_ebb(), Some(e2));
|
|
assert_eq!(cur.prev_inst(), Some(i3));
|
|
assert_eq!(cur.prev_inst(), Some(i2));
|
|
assert_eq!(cur.prev_inst(), None);
|
|
assert_eq!(cur.prev_ebb(), Some(e0));
|
|
assert_eq!(cur.prev_inst(), Some(i1));
|
|
assert_eq!(cur.prev_inst(), None);
|
|
assert_eq!(cur.prev_ebb(), None);
|
|
}
|
|
|
|
// Check `ProgramOrder`.
|
|
assert_eq!(layout.cmp(e2, e2), Ordering::Equal);
|
|
assert_eq!(layout.cmp(e2, i2), Ordering::Less);
|
|
assert_eq!(layout.cmp(i3, i2), Ordering::Greater);
|
|
|
|
assert_eq!(layout.is_ebb_gap(i1, e2), true);
|
|
assert_eq!(layout.is_ebb_gap(i3, e1), true);
|
|
assert_eq!(layout.is_ebb_gap(i1, e1), false);
|
|
assert_eq!(layout.is_ebb_gap(i2, e1), false);
|
|
}
|
|
}
|